If somebody works at Apple, they might have access to internal iOS code or knowledge of upcoming APIs which gives them an advantage over external app developers. The person working at Apple need not be part of iOS team. They could get hands on this internal information through grapevine, friends or being in a cross-team meeting.
In such cases, there are 2 options:
(i) Allow the apps from Apple developers, not label them as belonging to Apple and pretend that the app developer has no extra advantage over external developers. This seems misleading and wrong.
(ii) The apps from Apple developers should belong to Apple.